Radiation sources, for example, light emitting diodes (LEDs), usually have a comparatively small radiation exit area. The radiation generated by the radiation source can be coupled into a diffusor plate to enlarge the radiation exit area. However, this can lead to a comparatively inhomogeneous luminance on the radiation exit area, in particular with regard to the color locus and the emission angle.
It could therefore be helpful to provide a large-area emission with at the same time high homogeneity.